The Disposable class gives us a method to release allocated resources (database connections, file handlers, and so on). We can do this by calling the dispose() method  of this object.
In this section, we will use the dispose() method to unsubscribe from an observable.
To create a Disposable, we can use the create() function from Rx.Disposable:
var disposable = Rx.Disposable
.create(()=>console.log('Releasing allocated resources'));
disposable.dispose();
If you run this code, it will print the following message in your console:
Releasing allocated resources
As discussed earlier in this chapter, we can call the dispose() method to unsubscribe from an observable. In some cases, we can even define a Disposable to be used when someone calls the dispose() method from this observable (remember the create() and createWithDisposable() functions to create an observable).
The...
